Selecting a memory for storage of an encoded data slice in a dispersed storage network

• US 9,336,139 B2
• Filed: 11/07/2011
• Issued: 05/10/2016
• Est. Priority Date: 11/29/2010
• Status: Active Grant

• Current Assignee: Pure Storage, Inc.
• Original Assignee: Cleversafe Incorporated (International Business Machines Corporation)
• Inventors: Grube, Gary W., Markison, Timothy W.
• Primary Examiner(s): Shah, Sanjiv
• Assistant Examiner(s): Chappell, Daniel C
• Application Number:
  US13/291,042
• Publication Number:
  US 20120137091A1
• Time in Patent Office: 1,646 Days
• Field of Search: 711/158
• US Class Current: 1/1
• CPC Class Codes: G06F 12/0638 Combination of memories, e.g. ROM and RAM such as to permit replacement or supplementing of words in one module by words in another module address formation of the next microinstruction G06F9/26; masking faults in memories by using spares or by reconfiguring G11C29/70
• CPC Class Codes: G06F 21/6218 to a system of files or objects, e.g. local or distributed file system or database
• CPC Class Codes: G06F 3/0604 Improving or facilitating administration, e.g. storage management
• CPC Class Codes: G06F 3/0646 Horizontal data movement in storage systems, i.e. moving data in between storage devices or systems
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]

Abstract

A method begins by a processing module receiving an encoded data slice for storage. The method continues with the processing module obtaining metadata associated with the encoded data slice and interpreting the metadata to determine whether the encoded data slice is to be stored in a first access speed memory or a second access speed memory, wherein the first access speed memory has a higher data access rate than the second access speed memory. The method continues with the processing module storing the encoded data slice in a memory device of the first access speed memory when the encoded data slice is to be stored in the first access speed memory and storing the encoded data slice in a memory device of the second access speed memory when the encoded data slice is to be stored in the second access speed memory.

Claims

1. A method for execution by a storage unit of a dispersed storage network, the method comprises:

receiving an encoded data slice for storage;

determining whether to store the encoded data slice in a first access speed memory or a second access speed memory, wherein the first access speed memory has a higher data access rate than the second access speed memory, by;

determining an access frequency indicator based on access requests of other encoded data slices of a plurality of first encoded data slices stored by the storage unit for which access requests for the other encoded data slices were included in a decode threshold number of access request, wherein a plurality of data objects are dispersed storage error encoded into pluralities of sets of encoded data slices, wherein, for each set of encoded data slice of the pluralities of sets of encoded data slices, the decode threshold number of encoded data slices is needed to recover a corresponding data segment of one of the plurality of data objects, and wherein the plurality of first encoded data slices includes a first encoded data slice from each of at least some of the sets of encoded data slices of the pluralities of sets of encoded data slices;

when the access frequency indicator is less than or equal to an access frequency threshold, storing the encoded data slice in the second access speed memory; and

when the access frequency indicator is greater than the access frequency threshold, storing the encoded data slice in the first access speed memory.

2. The method of claim 1, wherein determining the access frequency indicator further comprises at least one of:

determining a data type of the encoded data slice, wherein, when the data type is a first data type, increasing the access frequency indicator such that the encoded data slice is to be stored in the first access speed memory;

determining a user identifier of the encoded data slice, wherein, when the user identifier is a first user type, increasing the access frequency indicator such that the encoded data slice is to be stored in the first access speed memory;

determining a priority requirement of the encoded data slice, wherein, when the priority requirement is a first priority type, increasing the access frequency indicator such that the encoded data slice is to be stored in the first access speed memory; and

determining a performance requirement of the encoded data slice, wherein, when the performance requirement is a first performance type, increasing the access frequency indicator such that the encoded data slice is to be stored in the first access speed memory.

3. The method of claim 1 further comprises:

the first access speed memory includes a plurality of solid-state memory devices; and

the second access speed memory includes one or more hard drive memory devices.

4. The method of claim 1 further comprises:

generating storage information to include one or more of;

a slice name associated with the encoded data slice;

a memory device identifier (ID) of a memory device of the first or the second access speed memory;

a memory device storage location associated with the storing of the encoded data slice; and

at least some metadata; and

storing the storage information in an information memory device of the first access speed memory.

5. The method of claim 1 further comprises:

determining that the access frequency indicator is less than or equal to the access frequency threshold when the other encoded data slices were included in the decode threshold number of access requests less than or equal to a value representing the access frequency threshold.

6. The method of claim 1 further comprises:

when the access frequency indicator is less than or equal to a second access frequency threshold, storing the encoded data slice in a third access speed memory, wherein the second access frequency threshold is less than the access frequency threshold, and the second access speed memory has a higher data access rate than the third access speed memory.

7. A computing device comprises:

a first module that, when operable in the computing device, causes the computing device to;

determine whether to store the encoded data slice in a first access speed memory of a second access speed memory, wherein the first access speed memory has a higher data access rate than the second access speed memory, by;

determining an access frequency indicator based on access requests of other encoded data slices of a plurality of first encoded data slices stored by a storage unit for which access requests for the other encoded data slices were included in a decode threshold number of access requests, wherein a plurality of data objects are dispersed storage error encoded into pluralities of sets of encoded data slices, wherein for each set of encoded data slices of the pluralities of sets of encoded data slices, the decode threshold number of encoded data slices is needed to recover a corresponding data segment of one of the plurality of data objects, and wherein the plurality of first encoded data slices includes a first encoded data slice from each of at least some of the sets of encoded data slices of the pluralities of sets of encoded data slices;

when the access frequency indicator is less than or equal to an access frequency threshold, storing the encoded data slice in the second access speed memory; and

when the access frequency indicator is greater than the access frequency threshold, storing the encoded data slice in the first access speed memory.

8. The computing device of claim 7, wherein the second module further causes the computing device to determine the access frequency indicator by one or more of:

determining a data type of the encoded data slice, wherein, when the data type is a first data type, increasing the access frequency indicator such that the encoded data slice is to be stored in the first access speed memory;

determining a user identifier of the encoded data slice, wherein, when the user identifier is a first user type, increasing the access frequency indicator such that the encoded data slice is to be stored in the first access speed memory;

determining a priority requirement of the encoded data slice, wherein, when the priority requirement is a first priority type, increasing the access frequency indicator such that the encoded data slice is to be stored in the first access speed memory; and

determining a performance requirement of the encoded data slice, wherein, when the performance requirement is a first performance type, increasing the access frequency indicator such that the encoded data slice is to be stored in the first access speed memory.

9. The computing device of claim 7 further comprises:

the first access speed memory includes a plurality of solid-state memory devices; and

the second access speed memory includes one or more hard drive memory devices.

10. The computing device of claim 7 further comprises:

a fourth module that, when operable in the computing device, causes the computing device to generate storage information to include one or more of;

a slice name associated with the encoded data slice;

a memory device identifier (ID) of a memory device of the first or the second access speed memory;

a memory device storage location associated with the storing of the encoded data slice; and

at least some metadata; and

a fifth module that, when operable in the computing device, causes the computing device to facilitate storing the storage information in an information memory device of the first access speed memory.

11. The computing device of claim 7, wherein the second module further includes operational instructions that, when executed by the computing device, causes the computing device to:

determine that the access frequency indicator is less than or equal to the access frequency threshold when the other encoded data slices were included in the decode threshold number of access requests less than or equal to a value representing the access frequency threshold.

12. The computing device of claim 7, wherein the second module further includes operational instructions that, when executed by the computing device, causes the computing device to:

when the access frequency indicator is less than or equal to a second access frequency threshold, storing the encoded data slice in a third access speed memory, wherein the second access frequency threshold is less than the access frequency threshold and the second access speed memory has a higher data access rate than the third access speed memory.